In the panic over measles’ spread in California and beyond, the public has been quick to blame vaccine refusers concentrated in wealthy, educated communities for being too ignorant to realize that measles can be a serious disease.

This charge, however, ignores the history of measles. It’s an intractable disease that, despite decades of vaccination, rebuffs our best efforts at elimination. And each time it flares up, its resurgence points out unresolved tensions between this country’s “haves” and “have-nots.”

When the first measles vaccine was released in 1963, vaccine developers and health officials were optimistic that it would be as widely used as the polio vaccine, which parents scrambled for when it first came out in the mid-1950s. But within just a few years, it was clear that only some segments of the population sought the new vaccine: predominantly white, middle- to upper-class families.

As a result, a California epidemiologist noted at the time, measles became “a disease of the Negro population and the population with Spanish surnames.” Across the country, measles began to cluster in poor urban areas. And as the decade progressed, the pattern only worsened.

When the Centers for Disease Control and Prevention announced a campaign to eradicate measles domestically via vaccination by the end of 1967, class disparities in measles infection rates provided part of the impetus. But the campaign, perhaps inadvertently, played to white, middle-class fears of diseases emanating from the “slums.” One cartoon depicted measles as a red-faced, yellow-eyed fiend who popped out of metal garbage cans left on the sidewalk and climbed through school windows to menace white children.

Nonetheless, the number of measles cases declined dramatically. But at the end of the 1960s they ticked up again. They were once again concentrated in urban "ghettos" and central city indigent areas. And blame for measles’ persistence was often placed squarely on the poor;  on their purported ignorance of the disease, on their lifestyles, even on their living conditions in new urban high-rise apartments, where tight quarters fueled the disease’s spread.

Laws requiring measles and other vaccines for school were adopted in the early 1970s, in part because they promised to address class disparities. As a CDC immunization official noted, “To reach the single preschool child in the slum is difficult, but to mount a campaign to attain really high levels of immunization in … school should be relatively easy.” And it was. President Jimmy Carter’s administration announced a renewed campaign to eliminate measles later that decade. By 1980, 96 percent of all children were vaccinated against measles and cases fell to an all-time low in 1981.

But by the end of the 1980s, measles again climbed to epidemic heights. And again cases concentrated among minority children in inner cities. President George H.W. Bush proposed tying welfare payments to children’s vaccination status; the outbreaks, in this view, were a matter of personal responsibility. Democrats, meanwhile, tied the outbreaks to a health-care system that shut out the nation’s poor.

New federal funds for vaccinating poor and uninsured children drove measles rates way down in the 1990s. In 2000, the CDC declared the disease "eliminated”: measles still occurred, but only when brought into the United States from abroad. In recent years, however, the size of measles outbreaks has grown, as has the number of cases coming in from outside the country.

As in the past, today’s vitriolic rhetoric around the causes of measles’ return tells us something about class relations in our own time. Blaming purportedly selfish upper-middle class families reflects a collective cultural discomfort with the wealthy’s increasing ability to opt out of shared responsibility for community welfare.

But as we focus on the alleged selfishness of wealthy, overeducated vaccine skeptics, other factors at the root of the outbreak are, as in the past, getting lost in the conversation. Parents avoid or delay children’s vaccines for an array of reasons: poverty, other challenges accessing health care, medical reasons, religious beliefs and an ever-expanding list of required vaccines. Parental acceptance of some immunizations has eroded in recent decades precisely because the overall number of vaccines and vaccine doses required for children has grown to historically unprecedented levels.

We need to acknowledge these factors — just as we need to recognize that our vaccination debates continue to thinly veil class anxieties deeply rooted in our history.

Elena Conis is an assistant professor of history at Emory University in Atlanta and the author of "Vaccine Nation."

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The CDC is urging people to get vaccinated for measles amid an outbreak that began at Disneyland and has now spread to other states, including Utah, Washington, Oregon and Colorado. (Reuters)